CN111743057A

CN111743057A - Additive-free coconut juice beverage and preparation method thereof

Info

Publication number: CN111743057A
Application number: CN201910240357.XA
Authority: CN
Inventors: 周海鹰; 李枚秋
Original assignee: Hong Kong Gelingbao Health Food Technology Co ltd
Current assignee: Hong Kong Gelingbao Health Food Technology Co ltd
Priority date: 2019-03-28
Filing date: 2019-03-28
Publication date: 2020-10-09

Abstract

The invention discloses an additive-free coconut juice beverage and a preparation method thereof, wherein the coconut juice beverage is prepared from the following components in percentage by weight: 6 to 50 percent of coconut milk, 1.0 to 2.0 percent of concentrated milk protein, 4.0 to 7.0 percent of cane sugar, 0.3 to 1.0 percent of trehalose and the balance of water; specifically, the concentrated milk protein is added into water to be dissolved, then is mixed with the heated coconut milk to be emulsified, sucrose and trehalose solution are added, water is added to the mixture to a constant volume, a high-pressure homogenizer is used for homogenizing once, UHT sterilization is carried out, the mixture is homogenized again under the aseptic condition, and the coconut milk beverage without the additive is prepared by aseptic filling, wherein the protein content is 1.0-2.0%, and the fat content is 2.0-3.5%.

Description

Additive-free coconut juice beverage and preparation method thereof

Technical Field

The invention belongs to the field of food preparation, and relates to an additive-free coconut juice beverage and a preparation method thereof.

Background

The fatty acid composition of coconut fat is 70% of medium-short chain fatty acids represented by lauric acid, which are considered to be healthy fatty acids. The coconut fat content in the coconut beverage is increased, so that the coconut flavor of the beverage can be improved, and the nutritional value of the beverage can be increased. Coconut pulp extracted from mature coconut meat has a fat content which is usually ten times of the protein content, and is very easy to float up due to the small specific gravity of the fat. At present, all coconut milk (coconut milk) beverages containing fat which are circulated at normal temperature on the market need to be added with food additives with emulsifying, thickening and stabilizing effects to prevent the phenomena of oil-water separation, fat floating, protein precipitation and the like after the beverages are stood for a long time.

At present, all natural coconut juice, recovered coconut juice, coconut milk and other various coconut flower color beverages added with fruit juice, coffee, cocoa powder and nuts in the market are prepared into beverages capable of being circulated and stored at normal temperature after emulsification, homogenization and sterilization because the coconut has high fat content and food additives with emulsification, thickening and stabilizing effects are required to be added. These beverages typically employ two or more of the following food additives, including: sodium caseinate (sodium caseinate), glyceryl monostearate, monoglyceride, diglycerol fatty acid ester, sucrose fatty acid ester, polyglyceryl fatty acid ester, sodium stearyl lactate, sodium carboxymethylcellulose, xanthan gum, gellan gum, etc.

Chinese patent document (application No. 201710049107.9) discloses a coconut juice without additive and a preparation method thereof, which declares that the coconut juice is prepared from the following raw materials: coconut milk 20-30%, coconut water 6-10%, white granulated sugar 15-20% and pure water in balance, without any emulsifier and preservative, simple process and equipment can prepare original coconut juice. However, this patent document does not describe how to prevent fat separation and floating up and to keep the coconut water stable during storage.

Disclosure of Invention

The invention aims to prepare a novel additive-free coconut milk beverage, pursues the natural and original ecology of food, relies on concentrated milk protein with excellent emulsifying property under the condition of not using any food additive, combines with advanced food processing technical equipment and process, solves the problems of short shelf life, poor appearance and character, poor taste, unstable storage of coconut milk caused by separation and floating of fat of the coconut milk beverage containing fat, and improves the nutritive value of the coconut milk beverage by adding milk protein with higher biological value. The invention provides a coconut juice beverage which comprises the following components in percentage by weight: 6 to 50 percent of coconut milk, 1.0 to 2.0 percent of concentrated milk protein, 4.0 to 8.0 percent of cane sugar, 0.3 to 1.0 percent of trehalose and the balance of water.

Wherein the sucrose is selected from one or more of white sugar, yellow granulated sugar, brown granulated sugar, soft white sugar, monocrystal rock sugar, polycrystal rock sugar, brown sugar, borneose, cubic sugar, sugar frost, and liquid syrup.

Further preferably, the coconut juice beverage comprises the following components in percentage by weight: 8 to 20 percent of coconut milk, 1.2 to 1.6 percent of concentrated milk protein, 5 to 6 percent of white granulated sugar, 0.4 to 0.7 percent of trehalose and the balance of water.

Further preferably, the coconut juice beverage comprises the following components in percentage by weight: 8 to 20 percent of coconut milk, 1.2 to 1.6 percent of concentrated milk protein, 6 to 7 percent of brown sugar, 0.3 to 0.5 percent of trehalose and the balance of water.

Further preferably, the coconut juice beverage comprises the following components in percentage by weight: 8 to 20 percent of coconut milk, 1.2 to 1.6 percent of concentrated milk protein, 3 to 4 percent of white granulated sugar, 3 to 4 percent of brown sugar, 0.3 to 0.5 percent of trehalose and the balance of water.

Wherein, the protein content in the coconut juice beverage is 1.0 to 2.0 percent, and the fat content is 2.0 to 3.5 percent.

The water is selected from one or more of purified water, natural mineral water, sterile water and the like; preferably, it is purified water.

Wherein the coconut pulp comprises any one or more of fresh coconut pulp, pasteurized coconut pulp, frozen coconut pulp, and the like.

The invention also provides a preparation method of the additive-free coconut juice beverage, which comprises the following steps: dissolving concentrated milk protein in water, mixing with coconut milk, emulsifying, adding sucrose and trehalose, homogenizing, sterilizing, and homogenizing under aseptic condition to obtain coconut juice beverage without additive.

According to the invention, the function of emulsified fat of the concentrated milk protein is utilized to replace the function of a food additive emulsifier, the fat in the coconut milk is emulsified through homogenization treatment, and the coconut milk beverage is homogenized for the second time after ultrahigh temperature instantaneous sterilization (UHT), so that the problems of fat floating, layering and the like do not occur in the storage process, and the coconut milk beverage is stable for a long time, preferably, the coconut milk beverage is stable for a one-year shelf life and does not have the problems of fat floating, layering and the like.

The method specifically comprises the following steps:

step 1): adding concentrated milk protein into water, stirring and dissolving to obtain a protein solution for later use;

step 2): adding sucrose and trehalose into water at the temperature of 50-90 ℃, and uniformly stirring and dissolving to obtain a sugar solution for later use;

step 3): heating coconut milk to 60-85 ℃ under the condition of stirring, then adding the protein solution prepared in the step 1), mixing and emulsifying to prepare a first milk A;

step 4): mixing the first milk liquid A prepared in the step 3) with the sugar liquid prepared in the step 2), uniformly stirring, and heating to 65-85 ℃ to prepare a second milk liquid B;

step 5): homogenizing the second milk B obtained in the step 4) for the first time, performing UHT sterilization on the homogenized milk, performing secondary homogenization under aseptic conditions after sterilization, and cooling to room temperature to obtain the additive-free coconut milk beverage.

Further preferably, the order of the above step 1) and step 2) of the present invention may be changed, for example, the above step 2) may be performed first, and then the above step 1) may be performed.

Further preferably, in the preparation method of the present invention, the step 3) and the step 4) can be combined into one step, that is, the following steps are adjusted: heating coconut milk to 60-85 ℃ under the condition of stirring, then adding the protein solution prepared in the step 1) and the sugar solution prepared in the step 2), mixing, emulsifying, and heating to 65-85 ℃ to obtain milk B'. The process flow can be simplified by combining the step 3) and the step 4) into one step.

From the viewpoint of emulsification effect, the effect of the stepwise preparation according to the above steps 3) and 4) is better than the effect of combining two steps into one step.

The term "emulsification" as used herein means that the fat in the coconut milk is dispersed in water under vigorous agitation to form an emulsion. The emulsification is carried out in a high shear emulsifier.

The additive-free coconut juice beverage comprises the following components in percentage by weight: 6 to 50 percent of coconut milk, 1.0 to 2.0 percent of concentrated milk protein, 4.0 to 8.0 percent of cane sugar, 0.3 to 1.0 percent of trehalose and the balance of water.

The concentrated Milk protein (Milk protein Concentrate) is also called Milk protein Concentrate, is Milk protein Concentrate, and is prepared by extracting and separating Milk by a physical method: after the skim milk is processed by an ultrafiltration membrane to retain milk protein, the skim milk is further evaporated, concentrated and dried to obtain a powdery milk protein product with multiple functional characteristics, the water content of the powdery milk protein product is less than 7 percent, the protein content is different from 42 to 92 percent, and the higher the protein content is, the lower the content of lactose and salt are. The difference between the concentrated milk protein and the prior art Sodium caseinate (also called Sodium caseinate Sodium calcium) for coconut milk beverage is that the Sodium caseinate is also a milk protein, but the Sodium caseinate is obtained by treating the casein curd of milk with an alkaline substance (such as Sodium hydroxide) to convert the water-insoluble casein curd into a soluble form, so as to prepare white or light yellow granules or powder. In the art, concentrated milk protein is used as a food material, while sodium caseinate is administered and used as a food additive.

The coconut milk of the invention is: peeling mature coconut fruit to obtain fresh coconut meat, washing with water, crushing, adding water or not, squeezing, and filtering. The pressed coconut milk can be directly used (fresh coconut milk), can be preserved for a short time after being cooled after pasteurization (pasteurized coconut milk), and can also be preserved for a short time after being frozen (frozen coconut milk).

When the coconut milk used in the invention is frozen coconut milk, in the preparation process, a proper amount of water is heated to 100 ℃, then the frozen coconut milk is put into the coconut milk, and then the coconut milk is heated to 60-85 ℃ under the condition of stirring to obtain hot coconut milk.

Wherein the mass ratio of the proper amount of water to the frozen coconut milk is 10 to (3-7); preferably, the ratio of the components is 10 to (4-6).

The actual amount of coconut milk used in the present invention will depend on the fat content of the coconut milk. Whether the coconut meat is crushed and squeezed with water or not and the proportion of the water added affect the fat content of the coconut milk. The coconut pulp prepared by crushing and squeezing the coconut meat without adding water has the fat content of 30-36 percent. The crushed coconut meat is pressed by adding water, so that the pressing yield can be improved, the maximum water adding amount can reach 6 parts of water added into one part of coconut meat, the fat content of the prepared coconut milk is changed along with the proportion of the added water, and the fat content can be changed between 4 and 30 percent. The coconut milk beverage has the fat content of 2.0-3.5%, and the amount of coconut milk in the formula can be calculated according to the fat content of the coconut milk.

The coconut pulp prepared by crushing and squeezing the coconut meat without adding water is pure coconut pulp, and the pure coconut pulp accounts for 6-12 wt% of the coconut juice beverage.

In the invention, the coconut pulp prepared by adding water into the crushed coconut meat and pressing is converted into pure coconut pulp accounting for 6-12 percent of the weight of the coconut juice beverage when preparing the coconut juice beverage.

Preferably, the crushed coconut meat is added with purified water with the weight of 4-6 times, the mixture is squeezed, and the fresh coconut milk with the fat content of 4% -7% is obtained through 100-200-mesh filtration and can be used for ingredient production.

Preferably, the crushed coconut meat is added with purified water 1-2 times the weight of the crushed coconut meat, squeezed, filtered by 100 meshes, pasteurized at 65-80 ℃ for 5-20 minutes, cooled to 4-10 ℃ to obtain pasteurized coconut milk with 10-15% of fat content, and can be preserved for 24 hours for later use.

Preferably, the crushed coconut meat is directly squeezed without adding water, and filtered by a 100-mesh filter to obtain high-concentration coconut milk with the fat content of 30-36%, and the high-concentration coconut milk is quickly frozen into frozen coconut milk which is stored for later use.

Wherein, the step 2) further comprises a post-processing step: the resulting sugar solution was filtered.

The filtering conditions are as follows: filtering with 100-300 mesh duplex filter.

Wherein, the step 3) is preferably emulsified by a high-shear emulsifying machine.

The emulsifying conditions are an emulsifying machine with the rotating speed of more than 1000rpm, an in-line emulsifying machine with the rotating speed of more than 1500rpm, and an in-line single-stage or multi-stage emulsifying pump with the rotating speed of more than 1500 rpm.

Wherein, the step of adding water to a constant volume is also included before the second milk liquid B is prepared in the step 4).

The purpose of the 'adding water and fixing volume' is to avoid that the concentration of the product is higher than a set standard due to the addition error of water in the operation process or the evaporation of moisture in the heating process.

Wherein, the first homogenization treatment and the second homogenization treatment in the step 5) are preferably carried out in a high-pressure homogenizer.

Wherein, the conditions of the first homogenization treatment in the step 5) are as follows: the low pressure is 30-50Bar, the high pressure is 200-300Bar, and the homogenizing temperature is 60-85 ℃; preferably, the low pressure is 50Bar and the high pressure is 250Bar, the homogenization temperature is 70-80 ℃.

Wherein, the condition for UHT sterilization treatment in the step 5) is as follows: the sterilization temperature is 136-146 ℃, and the sterilization time is 3-30 s; preferably, the temperature for sterilization is 138-142 ℃, and the time for sterilization is 5-15 s.

Wherein, the second homogenization treatment conditions in the step 5) are as follows: the low pressure is 30-50Bar, the high pressure is 60-200 Bar, and the homogenizing temperature is 60-85 ℃; preferably, the low pressure is 50Bar, the high pressure is 150Bar, and the homogenization temperature is 75-80 ℃.

Wherein the sterilization treatment in the step 5) is preferably UHT sterilization treatment.

The homogenization treatment of the present invention is carried out once before UHT sterilization and once after UHT sterilization.

When the existing coconut milk or coconut milk beverage containing the food additive emulsifier is produced by adopting a UHT process, the coconut milk or coconut milk beverage is usually homogenized once or twice before UHT sterilization, and due to the action of the manually added emulsifier, a stable emulsification system can be formed after one or two times of homogenization under the condition of reasonable formula, little small-particle coagulum generated by protein denaturation is generated in the process of ultrahigh-temperature instant sterilization, and the coconut milk or coconut milk beverage can be directly filled aseptically without being homogenized again under the aseptic condition.

In the invention, for a UHT production line provided with an aseptic homogenizer, when coconut milk or coconut milk beverage containing food additive emulsifier is produced, homogenization is not needed once before UHT sterilization, and due to the action of the emulsifier added manually, under the condition of reasonable formula, after emulsification by a high-shear emulsifying machine of a pre-procedure, a relatively stable emulsifying system can be formed, the milk can smoothly pass through UHT without influencing the heat transfer effect due to serious scaling inside the tube wall of a heat exchange tube, and in the process of ultrahigh-temperature instant sterilization, a small amount of small-particle coagulum generated due to protein denaturation can be directly filled aseptically after homogenization once under the aseptic condition.

The invention carries out the first homogenization treatment to ensure that milk protein and fat in coconut milk form a relatively stable emulsifying system, so that milk can not form scale inside the tube wall of a heat exchange tube to influence the heat transfer effect when the milk passes through UHT in the subsequent process. The invention carries out the second homogenization treatment to achieve the following purposes: in the ultrahigh-temperature instant sterilization process, a small amount of protein is denatured to generate small particle clots, and the small particle protein clots are homogenized again under the aseptic condition, so that the small particle protein clots are crushed and micronized to form a stable emulsifying system again.

According to the invention, the function of emulsified fat of the concentrated milk protein is utilized to replace the function of a food additive emulsifier, and the coconut fat is homogenized once before UHT and after UHT respectively, so that the coconut fat is fully emulsified and dispersed, and the problems of fat floating, layering and the like can not occur in the storage process of the produced coconut juice beverage. The UHT post-homogenization is aseptic homogenization and the coconut water beverage obtained after homogenization is aseptically filled, and the quality of the resulting coconut water beverage is stable for a prolonged period of time, such as a one year shelf life.

The invention also provides the additive-free coconut juice beverage prepared by the method.

The invention is obtained according to the following principle: the protein separated from cow milk has the function of emulsifying fat under proper conditions, and when the ratio of the protein to the fat is proper, a more stable emulsifying system can be obtained. However, these proteins are denatured and coagulated after heating at high temperature, and the emulsion system loses stability, resulting in oil-water separation, fat floating, protein precipitation, and the like. Experiments show that after being mixed with coconut milk according to a certain proportion, the protein separated from milk is emulsified by a high-shear emulsifying machine and is firstly homogenized by a high-pressure homogenizer, so that the protein and fat in the coconut milk form a relatively stable emulsifying system, and a large amount of protein flocculation can not occur in the ultrahigh-temperature instantaneous sterilization (UHT) process, and thus, the milk can be smoothly sterilized by the ultrahigh-temperature instantaneous sterilizing machine. During the ultrahigh-temperature instant sterilization process, a small amount of small-particle coagulum generated by protein denaturation can exist, and the coconut juice beverage after the ultrahigh-temperature instant sterilization is homogenized again under the aseptic condition, so that the denatured small-particle protein coagulum is crushed and refined, a stable emulsification system is formed again, and the beverage is endowed with delicious and smooth mouthfeel. The coconut milk beverage prepared by aseptic homogenization and the compound protein coconut milk beverage prepared by aseptic filling have the advantages of no oil-water separation, fat floating, protein precipitation and the like in the shelf life (12 months at normal temperature), good stability and convenient storage.

The invention has the beneficial effects that: the concentrated milk protein and the coconut protein contained in the coconut milk are added during the ingredients, so that the protein content in the beverage reaches 1.0-2.0 percent, and the beverage is more nutritious than the common coconut juice (the protein content is 0.5-0.7 percent); all the ingredients are food raw materials, and the food contains no additive components, so that the food is a very healthy food.

Detailed Description

The present invention will be described in further detail with reference to the following specific examples, but the scope of the present invention is not limited thereto. The procedures, conditions, experimental methods and the like for carrying out the present invention are general knowledge and common general knowledge in the art except for the contents specifically mentioned below, and the present invention is not particularly limited.

Table 1: raw materials and weight percentage content (%)

Examples 1-6 coconut juice beverages were prepared according to the following procedure, using the raw materials and weight percentages as indicated in Table 1

Step 1): weighing concentrated milk protein according to the formula proportion in the table 1, adding the concentrated milk protein into a proper amount of purified water, and stirring and dissolving to obtain a protein solution for later use;

step 2): weighing white granulated sugar, brown sugar and trehalose according to the formula proportion in the table 1, adding the white granulated sugar, the brown sugar and the trehalose into a proper amount of purified water at the temperature of 80 ℃, uniformly stirring and dissolving to obtain sugar liquid, and filtering the sugar liquid by a 200-mesh sieve for later use;

step 3): weighing coconut milk according to the formula proportion in the table 1, and heating to 70 ℃ under the condition of stirring to obtain hot coconut milk; among them, examples 5 and 6 used frozen coconut milk, which was obtained by heating a proper amount of purified water to 100 ℃ and then adding the frozen coconut milk, followed by heating to 70 ℃ under stirring.

Step 4): mixing the protein solution prepared in the step 1) with the coconut milk prepared in the step 3), and emulsifying by using a high-shear emulsifying machine to prepare a first milk A; wherein, the emulsification conditions of the high-shear emulsifying machine are as follows: emulsifying for 15 minutes by using a bottom-mounted emulsifying machine at the rotating speed of 1450 rpm.

Step 5): mixing the first milk A prepared in the step 4) with the sugar solution prepared in the step 2), stirring uniformly, heating to 75 ℃, adding purified water to a constant volume of 100% of the total amount of the formula, and preparing a second milk B;

step 6): placing the second milk B prepared in the step 5) into a homogenizer for primary homogenization treatment, wherein the conditions of the primary homogenization treatment are as follows: the temperature is 75 ℃, the low pressure is 50Bar, and the high pressure is 250 Bar; carrying out UHT sterilization treatment on the homogenized milk, wherein the sterilization temperature is 138 ℃, and the sterilization time is 15 s; and (3) carrying out secondary homogenization on the coconut milk from the UHT sterilizer in an aseptic state, wherein the conditions of the secondary homogenization treatment are as follows: low pressure of 50Bar, high pressure of 150Bar, homogenizing temperature of 75 deg.C, cooling to room temperature, aseptically filling, packaging, and warehousing.

Example 7 physical and chemical testing of coconut water beverages: the coconut milk beverages prepared in the embodiments 1 to 6 of the present invention were respectively tested for protein content and fat content, and the test results are shown in table 2:

TABLE 2 results of physical and chemical tests of coconut milk beverage prepared according to the present invention

As can be seen from Table 2, the coconut milk beverages prepared in examples 1-6 of the present invention all had protein contents greater than 1.0g/100g and fat contents greater than 2.0%, and were more nutritious than the conventional coconut milk (national and industry standards: protein content greater than 0.5% and fat content greater than 1.0%).

Example 8 sensory index of coconut water beverage: the coconut milk beverages prepared in examples 1 to 6 of the present invention were evaluated, and the evaluation results are shown in Table 3:

TABLE 3 sensory evaluation results of coconut milk beverage prepared according to the present invention

As can be seen from Table 3, the coconut juice beverages prepared in examples 1-6 of the present invention have a comprehensive score of more than 8 points, which is acceptable to the general consumers.

Example 9 Using the method of the present invention, coconut milk beverages prepared according to the above examples 1 to 6 were packed in 330ML tetra pak, and stored in a thermostat at 25 ℃ for 12 months, stored in an indoor natural temperature condition of Haikou city, Hainan province for 12 months, and stored in a general warehouse in Shanghai for 12 months, respectively, and the analysis results are shown in Table 4.

TABLE 4 quality of coconut milk beverage made according to the invention in storage period of 12 months

As can be seen from Table 4, the stability of the coconut juice beverages prepared in the embodiments 1-6 of the present invention meets the requirements of standards of QB/T2300-one 2006 vegetable protein beverage coconut juice and recovered coconut juice within a shelf life of 12 months.

Comparative experiment:

comparative examples 1-9 coconut water beverages were prepared according to the procedure shown in examples 1-6, based on the raw materials and weight percentages indicated in table 5.

Table 5: raw materials and weight percentage content (%)

TABLE 6 Experimental data on the influence of different raw material ratios on the mouthfeel and stability of coconut milk products

As can be seen from Table 6, the concentrated milk of comparative example 1 has a small amount of added protein, a low protein content, and insufficient ability to emulsify coconut fat, and the prepared coconut milk fat is easy to float upward, and the stability of the product is poor; the fat content of the comparative example 2 is low, and although the prepared coconut milk has good stability and the fat is not easy to float, the coconut flavor of the product is thinner due to the small addition amount of the coconut milk; comparative example 3 has high protein content, strong capability of emulsifying coconut fat, good stability of the prepared coconut milk, but poor taste of the product caused by adding excessive concentrated milk protein, sticky throat and unsmooth drinking; the coconut milk and the concentrated milk protein of the comparative example 4 are added in large amounts, the prepared coconut milk meets the requirements on stability, the coconut has strong fragrance, but the coconut has not tasty and refreshing mouthfeel, and the coconut feels sticky to the throat when being drunk; the coconut milk of the comparative example 5 has a large addition amount, the addition amount of 2.0% of concentrated milk protein is not enough to emulsify 4.0% of fat, the prepared coconut milk fat is easy to float upwards, and the stability of the product is not good; comparative example 6 appeared sweet and greasy due to high sugar content, and comparative example 9 appeared sweet and insufficient due to low sugar content; comparative example 7 and comparative example 8 coconut water was prepared astringent since there was no flavouring of trehalose.

Comparative test of technological parameters

Comparative example 10 coconut juice beverages were prepared according to the following procedure using the raw materials and weight percentages specified in the formulation of example 2 of Table 1

Step 1): weighing concentrated milk protein according to the formula proportion of example 2 in table 1, adding into appropriate amount of purified water, stirring and dissolving to obtain protein solution for use;

step 2): weighing white granulated sugar and trehalose according to the formula proportion of example 2 in table 1, adding the white granulated sugar and the trehalose into a proper amount of purified water at the temperature of 80 ℃, uniformly stirring and dissolving to obtain sugar liquor, and filtering the sugar liquor by a 200-mesh sieve for later use;

step 3): weighing fresh coconut milk according to the formula proportion of example 2 in the table 1, and heating to 55 ℃ under the condition of stirring to obtain warm coconut milk;

Step 5): mixing the first milk A prepared in the step 4) with the sugar solution prepared in the step 2), stirring uniformly, heating to 55 ℃, adding purified water to a constant volume of 100% of the total amount of the formula, and preparing a second milk B;

after the second milk liquid B is subjected to constant volume and is waited for subsequent homogenization treatment, the pH value of the second milk liquid B is detected to start to fall after 60 minutes, and the milk is tasted sour. The main reasons for this are: the treatment temperature of stirring and heating in the step (5) is lower (55 ℃), so that the heat-resistant microorganisms ferment and produce acid. The subsequent process is stopped.

Comparative example 11 coconut juice beverages were prepared according to the following procedure using the raw materials and weight percentages indicated in the formulation of example 6 of Table 1

Step 1): weighing concentrated milk protein according to the formula proportion of example 6 in table 1, adding into appropriate amount of purified water, stirring and dissolving to obtain protein solution for use;

step 2): weighing white granulated sugar, brown sugar and trehalose according to the formula proportion of example 6 in table 1, adding the white granulated sugar, brown sugar and trehalose into a proper amount of purified water at the temperature of 80 ℃, uniformly stirring and dissolving to obtain sugar liquor, and filtering the sugar liquor by a 200-mesh sieve for later use;

step 3): the frozen coconut milk was weighed according to the formulation of example 6 in Table 1, and added to 55 deg.C hot water, heated to 55 deg.C with stirring, to obtain warm coconut milk.

Comparative example 12 coconut juice beverage was prepared according to the following procedure, using the raw materials and weight percentages of the ingredients of the formulation of example 2 in table 1

step 3): fresh coconut milk was weighed according to the formulation ratio of example 2 in table 1 and heated to 90 ℃ with stirring to obtain hot coconut milk. The protein in the coconut milk was found to have particulate clumping at this point.

step 6): placing the second milk B prepared in the step 5) into a homogenizer for primary homogenization treatment, wherein the conditions of the primary homogenization treatment are as follows: the temperature is 75 ℃, the low pressure is 50Bar, and the high pressure is 250 Bar; carrying out UHT sterilization treatment on the homogenized milk, wherein the sterilization temperature is 138 ℃, and the sterilization time is 15 s; and (3) carrying out secondary homogenization on the coconut milk from the UHT sterilizer in an aseptic state, wherein the conditions of the secondary homogenization treatment are as follows: low pressure of 50Bar, high pressure of 150Bar, homogenizing temperature of 75 deg.C, cooling to room temperature, and aseptic packaging.

The packaged product was examined and the beverage was tasted as a non-smooth and grainy mouthfeel. After the product is kept stand for 1 month at normal temperature, protein particles are precipitated at the bottom. The main reasons for this are: the heating temperature of the pretreatment of the coconut milk in the step (3) is too high (90 ℃), so that the protein in the coconut milk is granulated and coagulated, and the taste and the stability of the beverage are still influenced though the subsequent homogenization treatment.

Comparative example 13 coconut juice beverages were prepared according to the following procedure using the starting materials and weight percentages given in the formulation of example 6 of Table 1

step 3): the frozen coconut milk was weighed according to the formulation ratio of example 6 in table 1, and added to hot water at 100 c, and heated to 70 c with stirring to obtain hot coconut milk.

step 6): placing the second milk B prepared in the step 5) into a homogenizer for primary homogenization treatment, wherein the conditions of the primary homogenization treatment are as follows: the temperature is 90 ℃, the low pressure is 50Bar, and the high pressure is 250 Bar; carrying out UHT sterilization treatment on the homogenized milk, wherein the sterilization temperature is 138 ℃, and the sterilization time is 15 s; and (3) carrying out secondary homogenization on the coconut milk from the UHT sterilizer in an aseptic state, wherein the conditions of the secondary homogenization treatment are as follows: low pressure of 50Bar, high pressure of 150Bar, homogenizing temperature of 90 deg.C, cooling to room temperature, and aseptic packaging.

The packaged product was examined and the beverage was tasted as a non-smooth and grainy mouthfeel. After the product is kept stand for 1 month at normal temperature, protein particles are precipitated at the bottom. The main reasons for this are: in the step (6), the medium process temperature is too high (90 ℃), and the protein is denatured and solidified, so that the taste and stability of the beverage are influenced.

Comparative example 14 coconut juice beverage was prepared using the raw materials and weight percents indicated in the formulation of example 6 in Table 1, as follows

Step 4): mixing the protein solution prepared in the step 1) with the coconut milk prepared in the step 3), and stirring and mixing for 15 minutes by using a stirrer with the rotating speed of 48 rpm.

The packaged product was inspected and the beverage tasted normally tasted. After the product is kept still for 3 months at normal temperature, the fat mass on the top of the beverage floats upwards. The main reasons for this are: because the step (4) does not adopt a high-shear emulsification process and only adopts subsequent homogenization process treatment, the stability of the prepared beverage cannot reach the shelf life of 12 months.

Comparative example 15 coconut juice beverages were prepared according to the following procedure using the raw materials and weight percentages indicated in the formulation of example 6 of Table 1

step 6): sterilizing the second milk B prepared in the step 5) by using a shell and tube UHT (ultra high temperature) for 15s at the sterilization temperature of 138 ℃; the coconut milk from the UHT sterilizer is homogenized in an aseptic state, and the homogenization treatment conditions are as follows: low pressure of 50Bar, high pressure of 150Bar, homogenizing temperature of 75 deg.C, cooling to room temperature, and aseptic packaging.

After the UHT continuously operates for 30 minutes, the temperature of the UHT sterilizer fluctuates, the temperature of feed liquid in the UHT pipe is reduced, the temperature of steam outside the UHT pipe is sharply increased, the pressure is increased, and the UHT system automatically alarms and stops. The UHT tubes were disassembled and fouling of the inner walls of the tubes was observed to affect heat transfer. The second milk B is not homogenized, the milk is not fully emulsified and directly enters the tube type UHT sterilization, and the milk loses stability at the high temperature of 138 ℃, so that the operation of a UHT system is influenced.

Comparative example 16 coconut juice beverage was prepared using the raw materials and weight percents indicated in the formulation of example 6 of Table 1, as follows

step 6): placing the second milk B prepared in the step 5) into a homogenizer for primary homogenization treatment, wherein the conditions of the primary homogenization treatment are as follows: the temperature is 75 ℃, the low pressure is 50Bar, and the high pressure is 250 Bar; and (3) carrying out UHT sterilization treatment on the homogenized milk liquid at the sterilization temperature of 138 ℃ for 15s, then cooling to room temperature, and carrying out aseptic filling, packaging and warehousing.

The packaged product was examined and the beverage was tasted as a non-smooth and particulate. Homogenizing the beverage in a homogenizer, homogenizing again at low pressure of 50Bar, high pressure of 150Bar and homogenizing temperature of 75 deg.C to obtain a beverage with good taste. It is explained that a small amount of fine particle clots generated by protein denaturation may also exist in the ultrahigh temperature instant sterilization process, and therefore, it is necessary to homogenize the protein particles again under aseptic conditions to pulverize and finely pulverize the denatured protein particle clots, thereby imparting a delicious and smooth mouthfeel to the beverage.

Comparative examples 17-24 coconut juice beverages were prepared according to the following procedure using the starting materials and weight percentages given in the formulation of example 6 of Table 1

step 6): homogenizing the second milk B obtained in step 5) in a homogenizer at 75 deg.C under the homogenizing pressure shown in Table 7.

TABLE 7 Experimental data on the effect of different homogenization pressures on the stability of coconut water product for the first homogenization

The centrifugal acceleration method is used for analyzing the emulsification stability, and the fewer sediments are at the bottom of the floating fat layer and the centrifugal tube, the better the stability is shown. Ordinary milk beverages are homogenized at low pressures, typically in the range of 30-50Bar, consistent with the experimental results of the present invention. The results of the experiments in Table 7 show that the suitable pressure for the high pressure part of the homogenizer for the first homogenization of coconut water according to the invention is 200Bar, 300Bar, most preferably 250 Bar. The homogenization pressure of the high-pressure part is low, the crushing effect is poor, fat balls are large, and the emulsification stability is poor; because the coconut milk of the invention is not added with an emulsion stabilizer, and only depends on the emulsification function of the concentrated milk protein, when the homogenization pressure of a high-pressure part is higher, the crushing effect is good, the diameter of the fat globule is small, the specific surface area is large, more emulsifier is needed to wrap the surface of the fat globule, the milk protein in the formula is insufficient, the surface of the fat globule can not be completely covered, the emulsification stability is reduced, and the phenomenon of 'homogenization over' is shown. The preferred homogenization pressure for the first time of homogenization of coconut water of this invention is: low pressure 50Bar and high pressure 250 Bar.

Comparative examples 25-29 coconut juice beverages were prepared according to the following procedure using the starting materials and weight percentages indicated in the formulation of example 6 of Table 1

step 6): placing the second milk B prepared in the step 5) into a homogenizer for primary homogenization treatment, wherein the conditions of the primary homogenization treatment are as follows: the temperature is 75 ℃, the low pressure is 50Bar, and the high pressure is 250 Bar; subjecting the homogenized milk to UHT sterilization at 138 deg.C for 15s, cooling to 75 deg.C, and performing second homogenization under the homogenization pressure shown in Table 8.

TABLE 8 Experimental data for the effect of different homogenization pressures on coconut water product stability for the second homogenization

The first homogenization before UHT has completed the process of crushing and emulsifying, the second homogenization is to crush again the fine particle coagulum generated by the denaturation of a small amount of protein in the process of ultrahigh temperature instant sterilization to make the beverage have smooth mouthfeel, so that high homogenization pressure is not needed, and the reduction of emulsion stability caused by excessive homogenization is avoided. The preferred homogenization pressure for the first time of homogenization of coconut water of this invention is: low pressure 50Bar and high pressure 150 Bar.

The components described in [0005] of Chinese patent document (application No. 201710049107.9) are used as raw materials: 20-30% of coconut milk, 6-10% of coconut water, 15-20% of white granulated sugar and the balance of purified water. Preferably, as stated in paragraph [0006] above, said coconut water comprises the following raw materials in weight percent: [0007] coconut milk 25%, coconut water 7%, white granulated sugar 17% and the balance purified water, the coconut milk is prepared under the experimental conditions of the invention, when the coconut milk passes through a UHT sterilizer, protein is seriously denatured and solidified, UHT can not continuously run for more than 1 hour, the produced product is seriously layered within one day, protein is precipitated, fat floats upwards, and the middle layer is clear water. The physical and chemical detection result of the product is as follows: 7.5% of fat, 0.7% of protein and 20% of soluble solid. The prepared coconut milk is tasted after being shaken evenly, has strong coconut flavor, but is very sweet and greasy, and is not suitable for being directly drunk as a beverage.

The protection of the present invention is not limited to the above embodiments. Variations and advantages that may occur to those skilled in the art may be incorporated into the invention without departing from the spirit and scope of the inventive concept, and the scope of the appended claims is intended to be protected.

Claims

1. An additive-free coconut juice beverage is characterized by comprising the following components in percentage by weight: 6 to 50 percent of coconut milk, 1.0 to 2.0 percent of concentrated milk protein, 4.0 to 8.0 percent of cane sugar, 0.3 to 1.0 percent of trehalose and the balance of water.

2. The coconut water beverage of claim 1 wherein the coconut milk comprises any one or more of fresh coconut milk, pasteurized coconut milk, and/or frozen coconut milk.

3. The coconut water beverage of claim 1 wherein said coconut water beverage has a protein content of 1.0% to 2.0% and a fat content of 2.0% to 3.5%.

4. The coconut juice beverage according to claim 1, wherein the sucrose is selected from any one or more of white sugar, yellow granulated sugar, brown granulated sugar, soft white sugar, single crystal sugar, polycrystal sugar, brown sugar, bornyl sugar, cube sugar, sugar frost, and liquid syrup.

5. A preparation method of additive-free coconut milk beverage is characterized in that concentrated milk protein is added into water to be dissolved, then the concentrated milk protein is mixed with coconut milk and emulsified, cane sugar and trehalose are added, then primary homogenization treatment and sterilization are carried out, and then secondary homogenization treatment is carried out under aseptic condition, so that the additive-free coconut milk beverage is obtained.

6. The preparation method according to claim 5, characterized by comprising the following steps:

step 5): homogenizing the second milk B obtained in the step 4) for the first time, performing UHT sterilization on the homogenized milk, performing second homogenization treatment under an aseptic condition after sterilization, cooling to room temperature, and performing aseptic filling to obtain the additive-free coconut juice beverage;

wherein, the sequence of the step 1) and the step 2) can be interchanged.

7. The method according to claim 6, wherein the steps 3) to 5) are performed as follows: heating coconut milk to 60-85 ℃ under the condition of stirring, then adding the protein solution prepared in the step 1) and the sugar solution prepared in the step 2), mixing, emulsifying, and heating to 65-85 ℃ to prepare milk B'.

8. The method for preparing the coconut milk beverage without the additive according to claim 5 or 6, wherein the weight percentage of each component in the coconut milk beverage without the additive is as follows: 6 to 50 percent of coconut milk, 1.0 to 2.0 percent of concentrated milk protein, 4.0 to 8.0 percent of cane sugar, 0.3 to 1.0 percent of trehalose and the balance of purified water.

9. The method of claim 5 or 6, wherein the coconut milk comprises any one or more of fresh coconut milk, pasteurized coconut milk, and/or frozen coconut milk.

10. The method according to claim 6, wherein in step 5), the conditions of the first homogenization treatment are as follows: the low pressure is 30-50Bar, the high pressure is 200-300Bar, and the homogenizing temperature is 60-85 ℃; and/or the conditions of the second homogenization treatment are as follows: the low pressure is 30-50Bar, the high pressure is 60-200 Bar, and the homogenizing temperature is 60-85 ℃; and/or the sterilization temperature is 136-146 ℃, and the sterilization time is 3-30S.